Gigantic Jet

Transient Luminous Event: Taken by Chris Holmes on October 15, 2019 @ Yucatan Peninsula, 35,000ft approximately 35 miles east of the cell.

CLOSE ENCOUNTER WITH A GIGANTIC JET


When you see lightning, run! That's what NOAA advises in lightning safety brochures. On Oct. 15th, however, pilot Chris Holmes had no place to go when lightning started to crackle in thunderstorms around his aircraft.

"I was flying 35,000 feet over the Gulf of Mexico near the Yucatan Peninsula when a super cell started pulsing with light," he says. "It wasn't just ordinary lightning, though. The cell was creating lots of sprites and jets leaping up from the thunderhead." At a distance of only 35 miles, he video-recorded this:


Comment: Video posted below.


"It was the most amazing thing I've seen in my aviation career," he says.

Holmes had a close encounter with a Gigantic Jet. Sometimes called "Earth's tallest lightning," because they reach all the way to the ionosphere ~50 miles high, the towering forms were discovered near Taiwan and Puerto Rico in 2001-2002. Since then, only dozens of Gigantic Jets have been photographed. In previous images taken by cameras on the ground, it's almost always impossible to see the base of the jet over the edge of the thundercloud. That's why Holmes's video is special. He was filming above the storm at practically point-blank range.

"His clip shows very nicely the top of the cloud where the jet emerges, which is usually hidden from view," says Oscar van der Velde of the Lightning Research Group at the Universitat Politècnica de Catalunya who examined the footage. "I split the video into individual frames so we can see exactly what happens."
gigantic jet
You can see the full sized image here or watch the video posted below.

Van der Velde's deconstruction reveals the order of events: "First, relatively cool blue filaments spring up. These are streamers akin to Saint Elmo's Fire," he explains. "Next, after the Jet reaches its maximum height, another feature crawls more slowly out of the cloudtop-a white-hot 'lightning leader.'"

Turns out, this is a bit of a surprise. For years, some researchers thought that Gigantic Jets could reach such extreme heights only if their streamers got a boost from the lightning leader. Holmes's video shows just the opposite: The Gigantic Jet reaches the ionosphere before the lightning leader even leaves the cloud.

"This suggests that there may be a much more powerful electric configuration inside the thunderstorm than was previously thought-perhaps as much as 200 million volts," says van der Velde.

SMOKEY PANCAKE SUNSET

On Oct. 25th, nature photographer Mila Zinkova watched the sun set from San Francisco, and it reminded her of breakfast. "The setting sun looked like a stack of pancakes," she says. This image is a still frame from a remarkable video:

pancake sunset

Novaya Zemlya effect sunset. Taken by Mila Zinkova on October 25, 2019 @ San Francisco, California, USA

Atmospheric optics expert Les Cowley explains what happened: "Sunsets like Mila's need a very strong temperature inversion where cold air is sandwiched between warmer air layers. The layers then act like a wave guide, ducting the sun's rays in layers. Short ducts give three pancake-like mirages. Very long ducts give the rare Novaya Zemlya effect with a whole shimmering stack of narrow stripes."

The colors of the sunset come from smokey wildfires currently raging through northern California. "There is so much smoke in San Francisco right now, I felt sure that images of the miraged sun would not be able to penetrate that smoky darkness of the duct just above the horizon," says Zinkova. "However, the sun won. It was like a miracle, a sign of hope that the fire will retreat."